Ioan Sanislav

Magmatic-hydrothermal processes and critical mineral (Sn-W-In-Sb) genesis in the Herberton Mineral Field

The Herberton Mineral Field and the surrounding area contains a large number of mineral occurrences enriched in highly sought after critical minerals (Sn-W-In-Sb). These mineral occurrences are spatially and temporarily related to intrusive and extrusive rocks of the Kennedy Igneous Province. However, the genetic link between igneous activity and mineralization is unclear whereas the processes leading to economic concentration of these metals are poorly understood. The main objective of this project will be to link igneous activity to metal enrichment and develop exploration criteria that can be used to discover new deposits. The project will involve field work in the tropical NE QLD coupled with extensive laboratory analyses involving a wide spectrum on analytical techniques.

Assessing alkaline magmatism in Mount Isa Inlier – the link to REE mineralization, the potential to host REE mineralization and tectonic significance

Syenite intrusive complexes are known to host economic REE mineralization and they are commonly enriched in REEs. The Mount Isa Inlier contains numerous mineral occurrence that are enriched in REEs but so far no major deposits have been found. Moreover, there are no satisfactory genetic models to explain the REE enrichment in the region.  Recent field mapping in the Mount Isa Inlier indicated that syenite intrusions are more widespread than currently shown on geological maps. Many of these intrusions occur as small gabbro-syenite complexes but some of them are volumetrically extensive. Field relationships indicate that they intruded at different times related to the tectonic activity. This project will involve field mapping in the Mount Isa Inlier, detailed petrology and mineralogy studies, age dating, geochemical modelling and the use of isotopes to understand the petrogenesis, tectonic setting and mineralization potential of these alkaline intrusive systems.

Lauren Waszek

Exploring Earth’s interior structure and dynamics beneath the Australian tectonic plate

While Australia is relatively seismically inactive, the plate boundaries display a range of stages of slab stagnation, making it an ideal natural laboratory. The aim is to combine observations from seismic waves which interact with mantle discontinuities with mineral physics modelling, in order to map the structures, thermochemistry, and dynamics beneath the region. The output will improve our understanding of the link between seismic discontinuities and deflection of convecting material.

Expanded project details – https://www.jcu.edu.au/__data/assets/pdf_file/0008/1888982/WaszekL2022.pdf

Multiple projects are available. Students with a computational background are encouraged to contact Lauren to discuss the projects in more detail.

Helen McCoy-West

Geochemistry and geochronology of titanite

(honours only)

This project will build on recently acquired preliminary titanite geochronology (ages) of intrusive rocks of the Mt Isa region. You will conduct additional analyses and compare the results to those from zircon geochronology studies of the same, or similar, rock samples. You will also investigate the differences in the geochemistry of older and younger titanite grains from the same sample, from which you could develop a scheme to determine primary and secondary titanite from its composition.

Melanie Finch

Critical metal fluid migration in shear zones during tectonic switches

This project aims to investigate why critical metal ore deposits form in inverted shear zones, which are zones of deformation that result from tectonic plates moving away from then towards each other. Depending on the student’s interests, this project could involve numerical modelling of inverted shear zones to determine drivers of ore fluid migration, which will be combined with investigation of inverted shear zones. Alternatively, the student can focus on known ore deposits that form within shear zones that have undergone switching. This project will generate a new understanding of how inverted shear zones pump fluids through rocks to cause enrichment and ore deposition. This type of deposit is common and the expected outcomes are improved exploration models, which should lead to discovery of new ore deposits, which is pivotal as the global demand for critical metals increases.

Feedbacks between high pressure metasomatism and structures in subduction channels

Subduction channels are ductile shear zones at the interface between the downgoing and overriding plate. These zones experience high fluid fluxes and cycle between ductile and brittle modes of deformation. Rock packages are often layered, with rocks from different P/T conditions juxtaposed, perhaps as a result of metasomatism. Detailed work is required to understand how the different rock types formed, and how metasomatism modifies the way rocks deform in these channels. This project will examine subduction channel rocks from Port Macquarie, NSW and New Caledonia to understand metasomatism and deformation at high pressure (blueschist and eclogite facies) using a combination of field work, structural geology, microstructures, petrology, and geochemical techniques.

Tectono-metamorphic evolution of the Barnard metamorphics, North Queensland

The Barnard metamorphics are the easternmost outcropping rocks in Northern Queensland, hypothesized to have formed on the eastern side of a suture zone. There has been very little work on these rocks, despite the outcrop being excellent and situated on the coast between Mission Beach and Cairns as well as on a number of beautiful tropical islands. Preliminary investigations reveal there is a complex structural history recorded in these rocks, with multiple overprinting events and melt-present deformation. This project will conduct detailed mapping, petrography, structural analysis and geochronology to determine how and when these rocks formed and what they can tell us about the final stage of assembly of Eastern Australia.